Heavy-duty caster



Feb. 3, 1931. w. G. JOHNSON- HEAVY DUTY CASTER Filed May 27, 1927 #f5 ation 74 /l/l/f .In .Z

45 5540 5 fl/l W im Patented Feb. 3, 1931 UNITED STATES PATENT OFFICE,

WILFBED G. JOHNSON, OF EIIYRIA, OHIO,

EIYRIA, OHIO, A CORPORATION OF OHIO HEAVY-DUTY CASTER Application filed May 27,

may, when desired, be disassembled or ad-k io justed relative to each other.

Another objectof my invention resides in the provision of an improved caster of a heavy duty type which is constructed of sheet metal to insure durability, having provision to render the same quiet in use,.and

wherein friction between the various parts comprising the saine and lateral stresses acting thereon are reduced to a minimum.

These and other objects' of my invention and the invention itself will become apparent from reference to the following description of an embodiment tlierein'a'nd in which description reference will be had to the accompanying drawings forming a part of this specification.

Referring to the drawings: Fig. 1 is a vertical, medial, sectional viewl of an embodiment of my invention, some of the parts being illustrated in elevation; 1

Fig. 2 is an end elevational view of the foregoing embodiment;

Fig. 3

is a side elevational view of a king` pin employed in the foregoing embodiment; and

Figs. 4 and 5 are fragmentary sectional, and plan views, respectively of a portion of foregoing embodiment.

Referring to all of the figures of the drawings, in all of which like parts are designated by like reference characters, and

wherein I have illustrated my improved caster preferably comprising a 'relatiyely large sheet metal caster supporting wneel 10 having a resilient rubber tire 11 disposed about the periphery thereofto insure quietness in use. This wheel is anti-frictionally rotatably mounted on an axle 13 by virtue of interposed ball bearing races 14.

The axle 13 projects through aligned openings in a pair of depending caster forks 18 1927. Serial No. 194,603.

and 19 and is secured therein by nuts 16 and `17. The caster forks formed with flanges 20 and 21 at their upper ends which ilanges are riveted at 22 and 23 to a caster race plate 24 to form a fabricated sheet metal caster yoke. A relatively enlarged upper bearing ball race plate 30 is secured by bolts 31 and 32 to a supporting article indicated at 33 directly above the lower plate 24 and is lconnected therewith by a king pin oi' bolt 50 and tubular bearing cone 55 which will be hereinafter described in detail.

' The bottom wall 34 of the upper plate 30 is provided with an annular groove 35 disposed directly above a similar annular groove 36 formed in the top wall of the lower plate 24. Said grooves are provided with annular concentric antifriction ball receiving concaved races 37 and 33, respectively, disposed between the side walls of the groove. A clearance 42 is so provided between the plates 24 and 30 of suiiicient size to receive a ball-bearing cage 39 having a plurality of bearing balls interposed therebetween out of contact with the plates, with the balls 40 carried therein disposed within the races 37 and 33 and spacing the upper and lower plates. .ii lubricant may be placed within the space 42 formed by the grooves to lubricate the bearing ball races. An annular felt washer 43 is compressed between the plates 30 and 24 and retained therein from lateral movement by the upstanding annular flange 44 and the depending annular flange 45, which flanges form the outer side walls, respectively, of the annular grooves 35 and 36 of the plates 30 and 24, respectively.

The caster yoke is preferably detachably secured to the upper plate 3() by virtue of the bolt or king pin 50 heretofore referred to, having a countersunk head 5l disposed within the countersunk aperture 52 of the top plate 30 and is provided with a threaded portion 54 extending downwardly through an axially aligned relatively large bore 53 in the lower plate 24. The lower threaded end 54 of the king pin 5() extends below the plate 24 but out of contact with the periphery of the tire 11 and is adapted to receive the tubular cone 55 threaded thereon.

Diametrically opposed recesses 5G and 57 are formed in the upper face of the top plate adjacent the countersunk apertureV whereby the countersunk head oi the bolt when placed in theA aperture 52 may be struck by a punch or any such suitable tool at portions adjacent the recesses 56 and 57 to press a portion 73 of the head into the recesses to lock the bolt in the countersunk aperture against rotation relative to the upper plate 30.

The cone has a cylindrical portion 70 extending upwardly through the bore 53 of the plate 24 intoan annular recess 58 and snugly engages the wall 7l thereof.` This recess is disposed in the center portions of Lthe plate 30 concentric with the countersunk openingr 52, andthe aligned bore in Vthe lower plate Q4. The upper interior wall peripheral edge ot the cone is inclined at G0, which'inclined wall receives the lower portion ot the countersunk heat 5l ot the bolt or king pin 50, whereby the cone and the pin engage each other and are prevented from tilting or undue relative lateral movement, but which are so related that rotative movement therebetweenis possible. A laminze of metallic shims 72 are interposed between the upper endof the cone and the upper tace oi' the recessto permit the cone to be adi usted relative to the king pin to take up any wear resulting from the bearing balls revolving in the ball races.

The lower end of the cone is formed withan integral castellated hexagonal nut (il, the slots 62 formed inthe nut which may be turned into alignment with atransverse bore 64 in the king pin 50 and a Cotter pin G3 may be disposed transversely ot' an opposed pair of the slots whenthe slots and bore have been aligned to hold the collar on the king pin.

A ball race 65 is formed on the exterior wall of the cone intermediate the endsthereof and directly above the castellated nut (1l. The race 65, when the cone has been mounted on the king pin, is disposed in the bore 53 of the `plate 24 concentric with the annular race groove 67 formed in the under tace ol the plate 24 and concentric with the bore A ball bearing cage 68 having a plurality of bea-ring balls 69 is interposed between the cone and the groove G7 to provide an antifrictional bearing.

A lubricant duct 76 may be provided in the plate 24, communicating` with the annular grooves 42 and with a lubricant valve lixture 77 ot a well known type which is adapted to receive. the nozzle of a lubricant supplying container to replenish the supply of lubricant to the caster when desired.

A slight clearance between the upper exterior wall ot' the collar provides a lubricant duct to enable a portion of the lubricant contained in the upper ball bearing race groove to flow downwardly into the lower ball bearing race groove to lubricate the same.

A caster constructed with a bolt or king pin 5() described in the foregoing embodies many advantages in that it is capable of being disassembled for replacement of worn parts. It is also possible that my invention embodies provision i'or adjustment nl the various parts comprising the same whereby any play between the wearing parts may be taken up readily` and effectively.

My improved caster is particularly applicable to hand trucks and the like which support heavy loads. I, therefore, contemplate constructing the various parts of the caster, of a pressed sheet steel and I also con template hardening the various portions ot the caster which are subjected to the greatest wear and thus insure durability and economy in construction.

The upper bearing balls l0 are so posi4 tioned relative to the plate 24 that they will receive nearly all of the direct load while the lower coi'lcentrically disposed bearing` balls support the remaining weight and at the saine time receive any lateral thrusts on the caster.

Although I prefer to mount the bearingballs in cages as illustrated and described, I sometimes contemplate disposing the bearing balls in the ball receiving groove with the cages omitted, by providing grooved races on both the upper and lower plate, a smooth working and more durable bearing is secured, whereby the wear ismore uniformly distributed and at the same time is reduced to a minimum.

The above describedconstruction will en able the caster to swivelabout a. vertical axis ment lsetup bythe lateral thrusts and stresses and the serviceability of the caster will be increased. 'L

Havingthus described my'invention in a speciiic embodiment' I am aware that numerous and extensive departures may be made from the embodiment herein illustrated and described, but without departing from the spirit ofmy invention. i

I claim:

l. In a caster adapted for heavy duty service, in combination, a top plate having an aperture therethrough, the lateralv walls ot the aperture converging toward a lateral side oif the plate, a caster fork having an apertured yoke recessed on its lower side concentric with its aperture, said top plate and yoke being in super-posed relation with their apertures in axial alignment, a king pin having a tapered head adapted to interiit closely with the converging walls oi saidplate aperture projected through both said apertures and recesses, a tubular bearing cone having ay lower annular flange screw threaded on to the lower end of the king pin and by an upper end adapted to adiustablv approach the said top plate, a plurality of signature this 14th thin, annular, sheet metal shims, of a selected number and thickness adapted to adjustably space the said upper end of the bearing cone from the lower side of said plate; a set of bearing balls interposed between the top plate and yoke and a second set of bearing balls disposed within the yoke recess between the yoke and said flange. v

2. In a caster adapted for heavy duty service, in combination, an apertured top plate recessed on its lower side, a caster wheel, a supporting fork having an apertured yoke recessed on its lower side concentric with its aperture, said top plate and yoke superposed with their apertures in axial alignment, a pin projected through both said apertures and recesses, removable spacing washer means susceptable of variation in thickness disposed within said plate recess, a tubular bearing` cone having an outwardly extending annular ange, spaced from one of its ends, adapted to be screw threaded onto the lower end of said pin, and engaging and adapted to tightly clamp said spacing washer means between its said end and the end wall of the plate recess, a set of bearing balls interposed between said top plate and said yoke, and a second pair of bearing balls disposed between said yoke and said flange and within said yoke recess.

In testimony whereof I hereunto affix my day of March, 1927. WILFRED Gr. JOHNSON. 

